Resistance to Deltamethrin inCulex pipiens pallens(Diptera: Culicidae) from Zhejiang, China

1 May 1999

journal article
research article
Published by Oxford University Press (OUP) in Journal of Medical Entomology

Vol. 36 (3) , 389-393
https://doi.org/10.1093/jmedent/36.3.389

Abstract

Resistance to deltamethrin, a pyrethroid insecticide, was found in 7 Culex pipiens pallens L. populations collected in Zhejiang (southeast China). Larval populations exhibited resistance ratios of 5.9–24.73 at LC₅₀ and of 95.8–294.5 at LC₉₅. Mortality ratios between field-collected adults and susceptible laboratory adults exposed to the discriminating dosage (0.01%/20 min) were 44.7–87.3. Resistance levels varied among populations as follows: Wenzhou>Ningbo>Hangzhou>Zhoushan>Jiaxing>Jinhua>Taizhou. Heavy use of pyrethroid insecticides for controlling mosquitoes in some areas has increased pyrethroid resistance in their regional populations. After selecting larvae from each population with deltamethrin for 12–15 generations, the resistance ratio increased by 103.3–342.5 at LC₅₀ and by 79.7–203.1 at LC₉₅. These results indicated that a large-scale Cx. p. pallens control with pyrethroid insecticides would induce a further increase of pyrethroid resistance in Zhejiang.

Keywords

This publication has 1 reference indexed in Scilit:

Efficacy of etofenprox against insecticide susceptible and resistant mosquito strains containing characterized resistance mechanisms
Medical and Veterinary Entomology, 1995